The Sitras PRO combined DC protective unit and controller is used in the power supply for DC railways in mass transit and main-line systems up 3,000 V DC. It protects DC switch gear and contact line systems against critical operating conditions and detects short-circuits during the current rise even before the maximum short-circuit currents are reached. Features Complete functionality in a single unit Protection Measurement Control Automation Flexible adaptation to system requirements Standard communication interfaces High-performance diagnostics, comprehensive event, alarm and measured value memory Compliance with all relevant standards Technical data (Central Unit / Human Machine Interface) Supply voltage Voltage range (±20 %) [V DC] [V DC] [V AC] Inputs / outputs Relay outputs** Digital inputs** Digital outputs** Analog inputs Analog outputs Fiber-optic inputs (connection to DC buffer amplifier) Service interface Permissible ambient temperature Operation Storage, transport [ C] [ C] 24...110 125 / 220 115 / 230 4 24 16 4 2 1 Ethernet -5...+55-40...+70 Maximum humidity (no condensation)* 95 % Degree of protection acc. to IEC 60529: 2003 Dimensions (Width x Height x Depth) Sitras PRO CU Central Unit Sitras PRO HMI Human Machine Interface * other values on request ** double these figures for the integrated PLC Option [mm] [mm] IP20 270 x 154 x 162 276 x 262 x 60 Sitras PRO DC protective unit and controller for DC traction power supply siemens.com/mobility
Overview The Sitras PRO secondary protection device has to be integrated into the protection concept of the entire DC traction power supply system. Product line The Sitras PRO product line consists of the following modules: Sitras PRO CU Central Unit Sitras PRO HMI Human Machine Interface Sitras PRO BA DC Buffer Amplifier Sitras PRO CM Cable Monitoring Module Sitras PRO SW PC User Software The Sitras PRO CU Central Unit is the heart of the product line. It supplies power to other modules, represents the interface to the system and performs protection and control functions. Hardware The modular Sitras PRO CU Central Unit is distinguished by the following architecture: Powerful 32-bit microprocessor system Fully digital measurement processing and control, from sampling and digitalization of the measured parameters to ON/OFF decisions for the circuit-breaker Complete electrical isolation and noise immunity of the internal circuitry from the measuring, control and supply circuits from and to the system. Sitras PRO integrated into the Sitras DSG DC switchgear Sitras PRO CU Central Unit 2
System configuration Busbar Measuring data acquisition Processor Operator Control and Monitoring Sitras PRO CU Central Unit Sitras PRO HMI Human Machine Interface Circuitbreaker Sitras PRO BAplus DC Buffer Amplifier Shunt Sitras PRO SW PC User Software Sitras PRO CM Cable Monitoring Module Screened feeder cable Contact line e. g. station control system Typical integration of Sitras PRO to the DC traction power supply Communication Numerous standardized interfaces and protocols provide flexible communication options for operation, parameterization, service, and time synchronization. Interfaces PROFIBUS RS 485 Ethernet, Fast Ethernet Fiber-optic cable (connection to Sitras PRO BA) Protocols PROFIBUS DP The Sitras PRO has also been prepared for future extensions, e. g. PROFINET 3
Basic functions Sitras PRO offers the following basic functions as standard: Overcurrent protection (I max ) This monitors the instantaneous current for a maximum current in the direction of incoming supply and in the direction of energy recovery. Tripping is initiated if one limit is exceeded for an adjustable period of time. Current surge protection (ΔI) The current surge protection samples the current rise and detects a fast current rise that is not consistent with any operating mode. The short-circuit is detected far below the peak current. This significantly reduces the load on the system. Current rate of rise protection (di/dt) The most distant short-circuit must be detected and isolated. This is done by initiating a tripping of the circuit-breaker if the set threshold for the current rate of rise is permanently exceeded and the adjustable period of time has elapsed. Overcurrent-time protection (I UMZ) The overcurrent-time protection detects currents that exist for a long time and are not consistent with any regular operating mode. The current is monitored in the direction of incoming supply and in the direction of energy recovery. Overvoltage/undervoltage protection (U max / U min ) When the outgoing cable voltage rises above or falls below a preset value and if this condition persists longer than the preset delay, a alarm and/or tripping is initiated. Contact line voltage monitoring This function is designed to monitor the voltage in the area of the supply and to generate a Voltage present message. Circuit-breaker failure protection The circuit-breaker failure protection verifies that a tripped circuit-breaker actually interrupts the current flow. Using a parameterizable signal, this allows tripping of an upstream medium-voltage circuitbreaker if necessary. Impedance protection The impedance protection monitors the resistance in the area of the supply and trips the circuit-breaker when resistance falls below a preset value. High-speed capacitor trip In combination with specially equipped circuit-breakers, the high-speed capacitor trip can be used to achieve even faster disconnection. Switching between protection parameter groups With up to five parameter groups, the Sitras PRO can be configured locally or remotely for the respective operating conditions. Event, alarm and measured value memories The unit is equipped with three different kinds of memory, each of which is organized as a circular buffer. The event and alarm memory saves the identifier in plain text, as well as value, source, date and time. With the help of Sitras PRO SW, the measured value memory can be used to analyze the current and voltage characteristics. Monitoring of cable insulation and cable screen break In combination with the Sitras PRO BAplus DC Buffer Amplifier and one or two Sitras PRO CM Cable Monitor Modules, the following faults can be detected: Insulation failure between the L+ conductor and the screen Insulation failure between screen and earth or the conductor L Screen break Different conversational languages The conversational language can be changed at any time between Chinese, English, German and Spanish. 4
Optional functions In addition to the basic functions there are a number of optional functions which can be implemented as subsequent upgrades. Control In addition to the protection function, the central unit is also capable of controlling the section test and the enabling of the circuit-breaker (test and automatic reclose function). This does not require any separate control. Another feature is the transfer trip function which trips the circuit-breaker in the neighboring substation or causes its own circuit-breaker to trip due to a transfer trip by the neighboring substation. Bypass disconnect interlocks are also provided on the bypass bus disconnector for the section feeder panels with bypass. Additional option: Another optional control function is the calculation of the residual section resistance based on the measured voltage contact line voltage and the test current. Integrated programmable logic controller (PLC) In addition to the dedicated control functionality of the central unit, the integrated PLC enhances the control unit with a freely programmable automation functionality, e.g. for the control of motor-operated disconnectors. This eliminates the need to use a separate PLC and ensures a uniform design of the control and protection equipment in the entire DC switchgear. The additional module makes a higher number of inputs and outputs available. Profibus DP and PROFINET communication The bus communication enables the transfer of status information, measured values, control commands and control parameters as well as the time synchronization. Advanced current rate of rise protection (di/dt adaptation) This continuously changes the I max value as a function of di/dt in order to achieve a significantly finer adjustment of the impedance protection and thus even faster disconnection in case of faults. Thermal overload protection The maximum permissible operating temperature of equipment may be exceeded in case of overload without the shortcircuit monitoring function detecting a fault. For this reason, the operating temperature of the contact line and/or the feeder cable can be monitored. Power/energy calculation This is based on the values of the incoming and recovered power as well as of the incoming and recovered energy of the section feeder. Storage of breaker loading (maintenance diagnostics) Various measured and calculated values (e.g. switching cycles, load integral) for the breaker loading are indicated. Additional conversational languages The standard conversational languages may be complemented with additional languages (up to eight). This may also include Asian or Cyrillic fonts. 5
Operator control and monitoring Sitras PRO can be controlled and parameterized by the operator: via the externally accessible Sitras PRO HMI - human machine interface, via the Sitras PRO SW PC User Software, or via one of the many communication interfaces using higher level control such as Sitras SCS-DC, Vicos or Simatic WinCC. Sitras PRO HMI Human Machine Interface The externally accessible human machine interface is integrated in a user-friendly manner in the door of the low voltage compartment of the DC switchgear. The features are Monochrome graphical user interface Ergonomic design Large keypad for convenient handling Individually parameterizable LEDs (functional assignment and text labels) Individually parameterizable function keys (functional assignment and text labels) Sitras PRO HMI externally accessible human machine interface 1 2 3 1 Individual text field 2 Five individually parameterizable function keys 3 Dynamic display of switch positions 4 Continuously updated display of the current and voltage 5 Status line with active message 6 Individually parameterizable LEDs for display of any process or device information 4 5 6 6
Operator control and monitoring Sitras PRO SW PC User Software Sitras PRO SW is a convenient tool that simplifies and accelerates operations and diagnostics from set-up and start-up of the equipment to analysis and documentation of system faults. The powerful software enables fast troubleshooting and provides valuable insights for possible action by the maintenance personnel. Sitras PRO SW is distinguished by the following features: included per default at Sitras PRO CU User guidance in familiar Windows design Easy parameterization with context menus drop-down lists for selection of applicable parameters display of limits for values Trace visualization Recovery function Print function Help function 7
Measured value acquisition Sitras PRO BA DC Buffer Amplifier The DC buffer amplifier is used for measuring the current and voltage while, at the same time, ensuring electrical isolation. The measured values are output to the Sitras PRO central unit via fiber-optic cable (FO). Analog outputs are also available, such as for the display of section feeder current for the display of section feeder voltage for the display of test voltage (voltage in the feeder section) Sitras PRO BAplus, the DC buffer amplifier, can also be combined with one or two cable monitoring modules to implement a cable monitoring function. Technical data for rated voltages 600...3,000 V DC Interfaces Analog outputs 3 FO output (connection to central unit) 1 FO inputs, only Sitras PRO BAplus (connection to cable monitoring modules) 2 Perm. ambient temp. (operation) -5 +60 C Perm. ambient temp. (storage) -40 +70 C Max. humidity (no condensation) 93 % Degree of prot. housing acc. IEC 60529 Degree of prot. terminals acc. IEC 60529 Width x Height x Depth IP40 IP00 200 x 123 x 84 mm Sitras PRO CM Cable Monitoring Module The cable monitoring module is designed to monitor screened feeder cables in traction power supply systems with positive contact line voltages of up to 1,500 V DC. It can be connected to any cable that has a concentric screen and conductor and an insulating outer sheath. The cable monitoring module is used for measuring the insulation resistance of the feeder cables. The cable screen can also be monitored for open circuit (breakage). The readings are sent to the central unit via the DC buffer amplifier. The cable monitoring module is connected to the central unit via the Sitras PRO BAplus DC buffer amplifier and is powered by the contact line voltage. A maximum of two cable monitoring modules may be used. Technical data for positive rated voltages 600...1,500 V DC FO output (connection to DC buffer amplifier) 1 Perm. ambient temp. (operation) -5 +60 C Perm. ambient temp. (storage) -40 +70 C Max. humidity (no condensation) 93 % Degree of prot. housing acc. IEC 60529 Degree of prot. terminals acc. IEC 60529 Width x Height x Depth IP40 IP00 100 x 118 x 84 mm Siemens AG Industry Sector Mobility Division Complete Transportation Mozartstraße 33b 91052 Erlangen Germany electrification.mobility@siemens.com www.siemens.com/mobility/electrification Siemens AG 2010 www.siemens.com Product Information / Version 1.2.3 / No. A6Z08110528236 The information in this document contains general descriptions of the technical options available, which do not always have to be present in individual cases. If not stated otherwise, we reserve the right to include modifications, especially regarding the stated values and dimensions.